The present invention relates to nutritional supplements prepared from plants of the genus Echinacea.
Numerous studies attest to the health-promoting properties of extracts derived from plants of the genus Echinacea. See, e.g., A. Awang and D. Kindack, Canadian Pharmaceutical Journal, 124: 512-516 (1991). There is a strong commercial market for Echinacea compositions containing biologically active components that are believed to promote good health. Further, it is desirable to formulate Echinacea compositions to contain standardized amounts of biologically active components derived from Echinacea plants. Such standardized, Echinacea compositions provide the consumer with a consistent, effective dose of one or more, biologically active, Echinacea components.
In particular, there is a strong commercial market for Echinacea extracts containing a high concentration of one or more, biologically active, Echinacea components believed to promote good health. Such highly enriched extracts can be used directly as dietary supplements, or can be blended with other Echinacea extracts to prepare dietary supplements containing standardized amounts of biologically active, Echinacea components.
Scientific studies indicate that Echinacea-derived polysaccharides, alkylamides and cichoric acid (a caffeic acid derivative also known as chicoric acid, 2,3-o-di-caffeoyl-tartaric acid) each possess health-promoting properties. For example, alkylamides from Echinacea have been shown to stimulate phagocytosis in mice granulocytes at concentrations of about 0.1 parts per million (ppm). Bauer, R. et al., Arzneim.-Forsch./Drug Research, 38: 276-281 (1988). Similarly, cichoric acid has been shown to increase phagocytosis in granulocytes, and may stimulate the immune system at concentrations as low as 0.01 ppm. See e.g., A. Awang et al., supra. Echinacea polysaccharides have been shown to inhibit hyaluronidase, increase phagocytosis, induce the release of interferon-6, and enhance resistance to C. albicans infection in mice. See, e.g., A. Awang et al., supra; Wagner, H, et al. Arzneim.-Forsch./Drug Research, 35: 1069-1075 (1985).
Numerous factors must be considered and optimized in order to produce Echinacea extracts having a high concentration of polysaccharides, alkylamides and/or cichoric acid. For example, the amounts of polysaccharides, alkylamides and cichoric acid in Echinacea plants are influenced by the species of the plant, the age of the plant and the plant growth conditions. Additionally, the solvents and process parameters, such as temperature and length of extraction period, utilized to extract polysaccharides, alkylamides and cichoric acid from Echinacea plants can greatly affect the yield of these components.
Thus, there is a need for methods for efficiently extracting polysaccharides, alkylamides and cichoric acid from Echinacea plants, and for Echinacea extracts containing a high concentration of polysaccharides, alkylamides and/or cichoric acid. Further, there is a need for standardized Echinacea compositions containing a predetermined, desired amount of Echinacea extracts, including polysaccharide, alkylamide and/or cichoric acid extracts.
In one aspect, the present invention provides Echinacea compositions including standardized amounts of at least two Echinacea components. More preferably the Echinacea compositions of the present invention include standardized amounts of at least three Echinacea components. In this context the term xe2x80x9cstandardized amountxe2x80x9d, or grammatical equivalents thereof, means a desired, quantified amount of an Echinacea component. Presently preferred Echinacea components are Echinacea polysaccharides, Echinacea alkylamides and cichoric acid. Presently preferred Echinacea extracts useful for preparing the Echinacea compositions of the present invention are extracts enriched in cichoric acid (most preferably cichoric acid prepared in accordance with the present invention), Echinacea alkylamides (most preferably Echinacea alkylamides prepared in accordance with the present invention) or Echinacea polysaccharides (most preferably Echinacea polysaccharides prepared in accordance with the present invention). The Echinacea compositions of the present invention can be in liquid form, gel form or solid form, such as a powder, or tablets, or capsules, and are preferably adapted for administration (more preferably oral administration) to a human being.
In another aspect, the present invention provides methods for preparing Echinacea compositions, the methods including the step of combining amounts of at least two Echinacea components, preferably three Echinacea components, sufficient to yield an Echinacea composition including standardized amounts of each of the combined Echinacea components. In this context the term xe2x80x9cstandardized amountxe2x80x9d, or grammatical equivalents thereof, means a desired, quantified amount of an Echinacea component. Presently preferred Echinacea components are Echinacea polysaccharides, Echinacea alkylamides and cichoric acid. Presently preferred Echinacea extracts useful for preparing the Echinacea compositions of the present invention are extracts enriched in cichoric acid (most preferably cichoric acid prepared in accordance with the present invention), Echinacea alkylamides (most preferably Echinacea alkylamides prepared in accordance with the present invention) or Echinacea polysaccharides (most preferably Echinacea polysaccharides prepared in accordance with the present invention).
In another aspect, the present invention provides methods for preparing Echinacea extracts enriched in at least one Echinacea component. The methods of the present invention for preparing enriched Echinacea extracts include the steps of selecting an Echinacea plant at a developmental stage having an enhanced amount of a desired component (such as cichoric acid, alkylamides or polysaccharides); selecting a portion of the plant that is enriched in the desired component, and contacting the selected portion with an amount of a solvent, selected from the group consisting of ethanol and water, effective to extract the desired component from the plant portion. Preferably the Echinacea extract is then concentrated. Any species of Echinacea plant can be utilized in the practice of the present invention, but the presently preferred species is E. purpurea. Extraction of Echinacea plant material utilizes a ratio (by weight) of plant material to solvent of no more than about two parts plant material to about one part solvent. The presently preferred ratio (by weight) of plant material to solvent is about one part plant material to about four parts solvent.
In yet another aspect, the present invention provides liquid Echinacea extracts enriched in one or more member of the group consisting of Echinacea polysaccharides, Echinacea alkylamides and cichoric acid. Presently preferred liquid Echinacea extracts enriched in polysaccharides include polysaccharides at a concentration greater than about 1% (w/w), more preferably greater than about 5% (w/w), most preferably greater than about 10% (w/w). Presently preferred liquid Echinacea extracts enriched in alkylamides include alkylamides at a concentration greater than about 0.1% (w/w), more preferably greater than about 1.0% (w/w), most preferably greater than about 3.0% (w/w). Presently preferred liquid Echinacea extracts enriched in cichoric acid include cichoric acid at a concentration greater than about 0.2% (w/w), more preferably greater than about 0.5% (w/w), most preferably greater than about 3.0% (w/w).
In yet another aspect, the present invention provides solid Echinacea extracts enriched in one or more member of the group consisting of Echinacea polysaccharides, Echinacea alkylamides and cichoric acid. Presently preferred solid Echinacea extracts enriched in polysaccharides include polysaccharides at a concentration greater than about 0.01% (w/w), more preferably greater than about 0.05% (w/w), most preferably greater than about 20% (w/w). Presently preferred solid Echinacea extracts enriched in alkylamides include alkylamides at a concentration greater than about 0.001% (w/w), more preferably greater than about 0.01% (w/w), most preferably greater than about 0.5% (w/w). Presently preferred solid Echinacea extracts enriched in cichoric acid include cichoric acid at a concentration greater than about 0.005% (w/w), more preferably greater than about 0.05% (w/w), most preferably greater than about 1.5% (w/w).
The Echinacea extracts of the present invention are useful, for example, as dietary supplements and as sources of polysaccharides, alkylamides or cichoric acid for blending to produce the Echinacea compositions of the present invention. The Echinacea compositions of the present invention are useful, for example, as human dietary supplements. By way of non-limiting example, when administered to a mammal the Echinacea compositions and extracts of the invention stimulate one or more of the following aspects of the immune system: macrophage phagocytic activity; nitric oxide production by macrophages; TNF-xcex1 production by macrophages; IFN-xcex3 production by splenocytes; and TNF-xcex1 production by splenocytes.
In yet another aspect, the present invention provides methods for enhancing immune system activity in a mammal. In one embodiment, the methods comprise administering to a mammal an effective daily dosage of an Echinacea composition comprising standardized amounts of Echinacea cichoric acid, Echinacea alkylamides and Echinacea polysaccharides. In another embodiment, the methods comprise administering to the mammal an effective daily dosage of an Echinacea extract selected from the group consisting of Echinacea alkylamides and Echinacea polysaccharides. The term xe2x80x9ceffective daily dosage,xe2x80x9d and grammatical equivalents thereof, means a daily dosage that is effective to enhance immune system activity in a mammal.